Concrete sawing machine having stabilizing wheels



R. TUCKER 2,973,950

CONCRETE sAwING MACHINE HAVING STABILIZING wHEELs March 7, 1961 6Sheets-Sheet 1 Filed March 27, 1956 n A 'Y n. A

IN V EN TOR. /Fy @Chef A TTR/VEY March 7, 1961 R. TUCKER 2,973,950CONCRETE sAwING MACHINE HAVING STABILIZING WHEELS Filed March 27, 1956 6Sheets-Sheet 2 NY w D N NN INVENTOR. Ra] Tue/fer MEM A T TUR/V57 March7, 1961 R. TUCKER 2,973,950

CONCRETE SAWING MACHINE HAVING STABILIZING WHEELS Filed March 27, 1956 6Sheets-Sheet 3 IN V EN TOR.

/ay Tac/fer ATTORNEY R. TUCKER 2,973,950 CONCRETE sAwING MACHINE HAVINGSTABILIZING WHEELS March 7, 1961 6 Sheets-Sheet 4 Filed March 27, 1956 AIN V EN TOR. /qy 70K/ref' A 7'7'0/'A/Ey R. TUCKER March 7, 1961 CONCRETESAWING MACHINE HAVING STABILIZING WHEELS Filed March 27, 1956 6Sheets-Sheet 5 ,.I ..l.l..MWI

E- S Q mv. Q mw I .mm N. m. mm. hm.

HUE la IN VEN TOR. /Pay Tac/fer,

ATTORNEY March 7, 1961 R. TUCKER 2,973,950

CONCRETE SAWING MACHINE HAVING STABILIZING WHEELS Filed Marohk27, 1956 6Sheets-Sheet 6 IN V EN TOR.

ATTORNEY nvited `States,Patent CONCRETE SAWING MACHINE HAVINGSTABILIZING WHEELS Ray Tucker, Kansas City, Mo., assignor to Robert G.Evans Company, Kansas City, Mo., a partnership Filed Mar. 27, 1956, Ser.No. 574,223

6 Claim. (Cl. 262-20) This invention relates to a machine for cuttingconcrete to make expansion grooves or for making repairs as in theconstruction and maintenance of concrete highways.

The principal object of the invention is to provide a I machine of thischaracter which is highly maneuverable but is exceptionally stable toassure accuracy of the cuts and to prolong the life of the cuttingblade.

Other objects of the invention are to provide for feeding the blade intothe work under power, and to quickly release the power when lifting theblade out of contact with the work, and to provide for accurate andstraightaway movement of the machine under power even when the machineis moving over rough, sloped or crowned surfaces.

In accomplishing these and other objects of the invention as hereinafterpointed out, I have provided improved structure, the preferred form ofwhich is illustrated in the accompanying drawings wherein:

Fig. l is a sideelevational view of a concrete cutting machineconstructed in accordance with the present invention and showing themachine in operation to cut an expansion groove in a concrete slab.

Fig. 2 is a plan view of the machine, parts of which are broken away andother parts shown in section, to better illustrate the construction.

Fig. 3 is a longitudinal section on the line 3 3 of Fig. 2, showing thecutting blade lifted out of the cut and the machine in transportposition.

Fig. 4 is a rear end view of Ithe machine with a part of the cowlingbroken away to better illustrate the parts covered thereby.

Fig. 5 is a horizontal section on the line 5-5 of Fig. 3, to betterillustrate the relative mounting of the cutting blade, the main tractionwheels, and the stabilizing wheels which cooperate with the tractionwheels ineliminating side sway and for maintaining accuracy of the cutproduced by the cutting blade.

Fig. 6 is a plan View of the friction drive unit.

Fig. 7 is a detailed perspective view of one of the side arms of thefriction drive unit.

Fig. 8 is an enlarged section on the line 8-8 of Fig. 4.

Fig. 9 is a fragmentary section on the line 9 9 of Fig. 8.

Fig. 10 is an enlarged detailed view of the controls for the speedtransformer and the friction drive unit, the movable parts of thecontrols being in position for effecting a forward movement of themachine.

Fig. l1 is a similar view but showing the controls moved to position forstopping forward movement of the machine.

Fig. 12 is a perspective view of the parts of the controls shown indisassembled spaced relation.

Fig. 13 is a fragmentary section on the line 13-13 of Fig. 1 showing themanner of mounting and securing the handle bars in adjusted position.

Fig. 14 is a cross-section on the line 14-14 of Fig. 5.

Referring more in detail to the drawings: 1 designatesV a machineconstructed in accordance with the present invention for producing cutsin concrete slabs to form expansion grooves or to cut out sections ofconcrete:

which extends transversely from one side of the framev to the other andhas its ends journaled in bearings 13 and 14. The bearings 13 and 14 arecarried in brackets 1S and 16 which are secured to the under side of theframe 2 at points spaced inwardly from the side members 5 and 6, as bestshown in Figs. 4 and 5. The wheels 10 and 11 are retained on the outerends of the axle 12 by collars 12' that are suitably pinned tothe axleas shown in Fig. 14. The main frame 2 is thus adapted to tilt on theaxis of the traction wheels 10 and 11 so that the forward end is loweredwhen the rear end is raised, as shown in Fig. 1, to carry the blade 3into and out of contact with the Work.

The blade 3 is carried on an arbor shaft 17 that extends transverselyunder the forward end of the frame and has its ends journaled inbearings 18 and 19 carried by brackets Ztl and 21 depending from theunder side of the frame 2 and which are preferably attached to theforward ends of the side members 5 and 6. The arbor shaft has reducedends 22 and 23 projecting outwardly from the sides of the bearings 18and 19 to form shoulders 24 and to mount the cutting blade 3 on one orthe other of the ends of the shaft, as desired. The cutting blade is inthe form of a disk of standard design and diameter to produce a desiredwidth and depth of cut. Usually the blades are of three standarddiameters, with a central opening of common diameter to pass over one orthe other ends of the arbor shaft and to be clamped thereon betweenclamping plates or washers 25 and 26,

the inner plates 25 being fixed to the arbor shaft andy backed by theshoulders 24 to seat the blade thereagainst for retention by an outerplate 26 when a nut 27 is turned onto a threaded terminal of the ends 22and 23. -To additionally secure the cutting blade,'the outer clampingplates carry dowel pins 28 (Fig. 5) that pass through a suitable openingin the blade and into registering openings in the inner plates 25, asshownV in Figs. 2 and 5.

The engine 4 is mounted on the main frame at a point substantially abovethe traction wheels with the power shaft 29 thereof extending parallelwith the arbor shaft and mounting a pulley 30 in registry with a pulley31 xed to the arbor shaft. The pulleys are preferably of themultigrooved type to accommodate a plurality of drive belts 32 thatoperate in the grooves of the respective pulleys and through a slot 33in the floor plate 9. The

of the frame 2, as best shown in Figs. 2, 4 and 5. Extending from theends of the axle 36 are spindles 37 and 38 mounting pairs of wheels 39and 40. wardly from the axle are spaced apart bars 41 and 42I andconnecting the ends thereof is a sleeve 43 whchis afnemen Mar. 7, 1961,

Extending forsleeyed upgnvthe axle 1 2 intermediate the bearings 13 and14, whereby the pairs of wheels 39 and 40 trail the traction wheels. Thebars 41 and 42 are rigidly braced with respect to the sleeve 43Aand-axle 36 by a transverse Plat@ 4.4 that is Secured along the rearSide. of the sleeve 433111110 thensr faces of the bars41. and 42.Cooperating with the plate 4 4 but on the outer sides ofv the bars 41and 42 a-re braces 45 and 46 having their rear ends fixedto the axle 36at points` spaced outwardly from the rear ends of the bars 41 and 42 andtheir forward ends fixed to the outer faces of the bars immediatelyadjacent the ends of the sleeve 4 3. The braces 45 and 46 areadditionally connected with the outer ends of the axle 36 by gussets 47and 4. The sleeve 43 is preferably secured to the axle shaft by setscrews l49 and 50 whereby the axler 12 turns within hubs of the tractionWheels 10 and 11. when the pairsv of. wheels 39 and 40 roll upon unevens u rfvaces The axles, remain in substantially rigid parallelrelationand the wheels provide a four-point support with the dollywheels spaced widely apart to eliminate lateral swayfand to maintain astable, straightaway course for the cutting blade when the machine is inuse,v as later described.` The dolly is connected with a rear part ofthe main f rarnel by means ofY a manually actuated power lift, as laterdescribed,rwh ereby the rear end of the main frame 2 may be raised andlowered to tilt the frame 2 for carrying the cutting blade 3 into andout` of contact with the. WQrkf Extending upwardly from the rear portionof the main frame is a cowl and handle assemblySl comprising sidemembers 52 and53 each of which is formed of tubular stock to provideforward legs 54, having lower ends 55 ywelded to the main frameforwardly of the rear end members. The legs 54 extend upwardly andrearwardly at an angle with respect to the side members and terminate inrearwardly extending bar portions 56 to connect with rear legs 7 thathave upper portions 53 extending downwardly inparallel relation with thefront leg portions and that havel lower portions 59 extending downwardlyand forwardly at an angle to connect with the rear corners ofV the mainframe 2. The front and rear legs are connected on their inner s idefaces by plates 6) and'61 which extend from the floor plate 9upwardly toterminate short of the bar portions 56 to support a cowl 62therebetween.

The cowl 6 2 comprisesI a plate that is shaped to provide azrfnorwardskirtJ portiong, atop 64and a rear skirt portion 65 following the formof the upper ends of the side plates 6 0 andl, as best shown in Figs. 3and 4. Fixed` to the inner sides of the side plates and extendingthrough the front and rear skirt portions of the cowlare tubular guides`66V and 67 to mount handle bars 63 and v69 that slide therein; in thefore and aft direction of the machine to project the rear ends when itis desired to use them, The rear ends of the handle bars are providedwith suitable hand grips 70. The handle bars are adjustably secured inthe'guides 66 and 67 by clamp screws 66 having hand wheels 67' Yby whichthey may be easily manipulated (Figs. l and 13).

' The side members are connected substantially midway kof their heightby a transverse bar 71 which cooperatesv withv the axle 36 in connectingthe power lift previously Y referred to. The power lift in theillustrated instance is.

a hydraulic jack 72 including acyliiider 7 3 and a ram '74 which slidesin theV cylinder.' The ram 74 has its lower endpivotallyconnected-withspaced apart. lugs 75 (Fig.

4) extending upwardlyfrom the axle V36in a point substantallyl midwayofthe length thereof, the pivotal connection being made by aV transversepin 76 that extends throughy the spaced lugs 75 and through anintermediate lug 77on thewlower endv of the ram. The cylinderr'73slides. oventhe upper endofthe ramV and connects by means of atransverse pin 78with1ugsl79 projecting rearwai-idly. froirithe.transversesbar- 71, as besttshown--in Figs.r Stand 4.` The-tram. 74..is preferably4 protected by a y is forcedr under pressure of the pumplthrough a. flexible duct 83 that connects the pump with the upper end ofthe cylinder 73, as best shown in Fig. 3. The pump is actuated by meansof a handle 84 that projects rearwardly through a slot 85 in the rearportion 65 of the cowl to carry a hand grip 8 6 in convenient reach ofthe operator of the machine. Pressure created by the pump is released bymeans of a valve (not shown) but which is located in the case 81 and iscommon to such hydraulic mechanisms. The valve is operated by a shaft 87which extends from the case through the rear portion of the cowl andcarries an actuatinglever 88. When the pump handle 84 is manipulated toactuate the pump, hydraulic duid is forced under pressure through theduct 33 into the upper end of the cylinder 73 to act between the head ofthe cylinder and, upper end of the ram, whereby Va downward force isexertedl on. the axle 361 and an upward force is exerted on the crossmember i1 to tilt the mainframe on the traction wheels 10 and 11 andsuppoit the rear end of the main frame 2 on the dolly while the cuttingblade 3 is being operated to lmake a cut of a desired depth, as laterdescribed.

The machine is adapted to be operated in a forward direction byfrictional Contact of drive wheels 89 and 9.0 with treads of thetraction wheels as shown in Figs. 1,2 and 3. The drive wheels. 89 and9i) are carried. on a transverse shaft 91. The shaft 911 is journaled inbear.-

ings 92 and 93 that are adjustably mounted on arms 94 and 95, the arms914 andi 95 being pivotally connected' between pairs ofV ears 96 and 97depending from the under opposite sides of themain frame 2 substantiallyat points above and to the rear ofthe axle 12, as shown in Figs. 2 and3. The rear ends ofthe arms 94and95 are connected by a crossbar 97whereby botharms are moved as a unit to` bringthe drive wheels intofriction contact with the treads of the traction wheels, as laterdescribed. In order to adjust frictional contact of the driving wheels89 and 9h' with the traction wheels 1 0 and 11, the bearings 92 and 93are adjustably mounted on the arms by means of jack screws 98 .that maybe threaded in openings provided in downturned ends 99 of the arms andwhich are connected with the bearingsin which the drive shaft isjournaled. lt is obvious that by turning of the jack screws the bearingsmay be moved along the under sides of the arms to adjust pressure of thecontact between the drive'wheels39 and 90 and the traction wheels lfand11.

(')arried on a platform 9' above the door plate of the rnain frame is aspeed transformer 169 having a power input shaft 101 which is adapted tobe operated from the power shaft of the engine through a belt 102, thebelt 102 operatingover a pulley 103 on the power shaft of the engine andover a pulley 184 on the power input shaft of the speed transformer; Thespeed transformer has a shaft 105 extending from the opposite side andconnected through a coupling` 1526 with the power input` shaft of achange speed gear unit 167 whereby the gear unit may be operated at anyspeedV from zero to the maximum speed of the speed transformer 16) uponmanipulation of the shift lever 108 of the speed transformer. The outputshaft 109 of the gear unit 107 carries a sprocket 110 and operating overthe sprocket and a similar sprocket 111 on the shaft 91 isa chain 112 toconnect the drive shaft with the engine to move the machine in afor-ward direction, the chain operating through an open: ing 113 of thefloor plate 9 and an idler sprocket` 111'V on the crossbar 97.

- It; isy necessary -tof'supply the-cuttingbladefy with streams of waterthat are discharged on the-.respective sidesof the blade, as now to bedescribed. The cutting blade iS therefore preferably enclosed on theupper side with a guard 114 having sides 115 connected by a rounding top116. The sides and top are also shaped to provide rear extensions 117 tosuspend a splash guard 118. The guard 114 is pivotally mounted on one orthe other of the side members of the main frame by a bolt 119 thatextends through a sleeve 120 fixed to-the extension 117. The guard 114is thus hingedly mounted so as to be swung retractively from coveringrelation with the cutting'blade, as when changing blades. The guard 114is supported on hooks 121 (Fig. 3) that engage the inner lower edge ofthe guard at a. point forwardly of the arbor shaft 17. The guard isclamped in the hook by a clamp nut 122 on a stud 123 projecting upwardlyfrom the sides of the main frame 2. Fixed to the top of the guard andextending thereacross on the respective sides of the stud 123 are spacedbars 124 that are adapted to be engaged by the nut 122. Since the guardisl adapted to either side of the machine, each side has a stud 123 anda threaded opening for the bolt 119.

Mounted on the guard is a T-ftting 125 having laterally extending Ls 126which project over the sides of Ithe guard to connect with hose 127leading to nozzles 128 carried by the sides 115 of the guard, as shownin Figs. 1 and 2. Connected with the other branch of the T-fitting is ahose 129 that connects with a valve 130 which in turn is connected bymeans of a hose 131 with the pressure outlet connection 132 of a pump133. The pump 133 has a suction connection 134 that is adapted to beconnected by a hose (not shown) with a source of water supply (also notshown). The pump 133 is mounted on an extension 99 of the platform andrearwardly of the variable speed transformer 100. The pump 133 isactuated from a pulley 135 on the input shaft of the transformer andwhich carries a belt 136 operating over a pulley 137 on the pump shaft138.

When the machine is to be guided by the handle bars, it is necessary tolift the dolly to clear the wheels thereof. This is effected by means ofa spring 139 seated on fthe floor of the main frame at a point over thetransverse axle 36 and which spring 139 is enclosed in a tubular housing140 having its lower end fixed to the floor of the main frame and itsupper end terminating below the top 62 of the cowl, as best shown inFigs. 4 and 8. Carried on the upper end of the spring is a collar 141 towhich is connected a cable 142 that extends downwardly through thespring 139 over a guide pulley 143 to connect with a lug 144 on the rearof the transverse axle 36, as shown in Figs. 4 and 8. The length of thecable 142 is such that when the main frame is in horizontal position thespring 139 is compressed to give the action necessary to lift the dolly35 after the fluid pressure in the hydraulic jack 72 has been released.When the jack 72 is operated to in effect lengthen the jack connectionbe- -tween the main frame 2 and the axle 33 of the dolly 35,

lthe spring 139 is held down by the cable and is compressed to assist inreturning the main frame 2 to horizontal position upon release of thehydraulic fluid from the cylinder 73 into the case 81.

This mechanism also performs an important function of actuating anindicator drum 145 which indicates the depth of cut made by a givendiameter of cutting blade 3. The drum 145 is rotatably mounted on atransverse pin 146 which is supported below the top portion 62 of thecowl by brackets 147. The brackets 147 are suitably attached to theunder side of the cowl and have depending flanges 14S to journal theends of the pin 146. The drum has a peripheral scale 149 for eachdiameter of blade to be used, for example, the ordinary lblades employedin connection with machines of this character are 12, 14 and 18 inches,and therefore the drum has three scales 149 wherein the graduationsthereof arev re- '.Spectively visible through windowopenngs 150 in thetop portion62 of the cowl. `The indicator drum 145 is operated in onedirection by a cable 151 having one end attached to the collar 141 andthe other end is wrapped laround the drum within a groove 152 and isanchored in aV side'of the groove in such a manner that when the mainframe 2 is pivoted to bring the cutting blade 3 in contact with thework, the movement thereof from the normal position results in thecollar 141 pulling on the cable 151 to rotate the drum a distancecorresponding with the depth of cut of the cutting blade 3, consequentlythe graduation appearing in the proper window visibly indicates thedepth of the cut. During rotation of the indicator drum to indicateposition, a spring 154 is loaded to return the drum to zero position atthe time the frame is returned to a position that results in lifting ofthe blade from the cut. The spring 154 is connected with a clip 155 thatis carried von one side of the tubular housing 140, as shown in Figs. 4and 8. The other end of the spring 154 is connected by a cable 156 thatoperates ina second groove 157 in the indicator drum and which isanchored thereto so that when the rear of the platform is lowered tolift the cutting blade out of the cut, the spring 139 expands, tendingto make slackthe cable 151, but the slack is immediately taken up bycontraction of the spring 154 to furnish the action necessary to rotatethe indicator drum to Zero position.

Forward travel of the machine is effected by contacting the drive wheels89 and 90 with the traction wheels 10 and 11, and the motion of themachine is stopped by lifting of the drive wheels 89 and 90 from contactwith the traction wheels 10 and 11. This is effected by means of a handlever 158 located on the outer side of the side member 53. The lever 158is pivotally mounted on a screw 159 that is carried by a bracket 160fxedto the forward leg 54 of the side member 53. Reciprocably mounted in abearing portion 161 of the bracket 160 is a rod 162 having one end 163connected with the lever 158 by links 164. The other end 163 of the rod162 is connected by means of a turnbuckle 165 with a clevis 166 which ispivotally connected by a pin 167 to an arm 168 of a rock shaft 169. Therock shaft 169 extends transversely of the machine and has its endsjournaled in bearings 170 and 171 that are carried by the forward legs54 of the side members 52 and 53. Projecting forwardly from the rockshaft is an arm 172 which is pivotally connected by means of a link 173lwith an arm 174 on the bar 97. Thus by lifting on the lever 158 theshaft 169 is rocked in a counterclockwise direction to lower the drivewheels 89 and 90 into driving contact with the treads of the tractionwheels 10 and 11 to effect forward movement of the machine. When thelever 158 is moved in the opposite or clockwise direction (Fig. 1), theshaft 169 is rocked in the opposite direction to lift the drive wheelsfrom contact with the treads of the traction wheels to stop forwardmovement of the machine under power of the engine 4.

The shift lever 108 for the speed transformer- 100 is actuated by alever 175 also pivotally mounted on a part 176 carried by the bracket160. Fixed to an extension 177 of the part 176 by fastening devices suchas screws 178 is a guide 179 for a cable 180. Thev cable 180 isslideably contained in a sheath 181, so that it may be movedlongitudinally therein to transmit motion of the lever 175 to the shiftlever 108, the ends of the cable being suitably connected to therespective levers.v When the lever 175 is moved in a counterclockwisedirection, the shift lever of the speed transformer is moved to zeroposition, and when the lever 175 is moved in a clockwise direction, Fig.1l, the'shift lever 108 of the speed transformer 100 is shifted toincrease the speed of the output shaft. In order that the maximum speedto be effected by the lever 175 may be set automatically, the lever 175has a lug 182 that connects with a rod 183 which is slideable in-anlopening 184 in an ear 185 that projects from the plate 61. The rod 183is threaded as indicated at 186 and carries stop and jam nuts 187 and188 so thatA when the lever` 175 is` in position; for the desired speed,the stop nut 187 maybe adjusted on the rod toV engage the` rear side of;the ear 185, as shown in Fig. ,10, and the stop nut 187 ist lockedV byturning the jam nut- 188 thereagainst. With this'rarrangement, the lever175 may be shifted from the maximum speed desired toy neutral speedandback to the desired speed without adjusting the position thereof, itbeingA only necessary to shift the lever to the position where it isstopped by engagement 'of the nut 187 with the ear 185; With thecontrols thus far described, the levers 158 and 175 may be operatedindependentlyof each other,4

andv therefore the speed change lever 175 may be in posif tion where theshift lever 108 on the speed transformer 1,00 is not'in zero position.rfherefore, when the lever 158` is operatedA to bring the drive wheels89 Vand, 90 into contact withY the treads `of the traction wheels 10 and11, an excessive shock is applied tothe power units 106` and 107, withthe result that one or both power units may be severely damaged. Toavoid this difficulty, the lever' 158 has an arm ISS, thereon that has alaterally extending lug 1-89 adapted to engage a laterally extending lug190 on the lever 175. Therefore, when the lever 158 is moved all the waydown, Fig. 1l, the lug 189 thereon engages the lug 19d on the lever 175Yto automatically move the lever 175 of the speed transformer to neutralposition. Therefore,` when the lever S is raised to reengage the powerldrive of the' traction wheels, the lever 175 remains in neutral positionandit is impossible `to start movement of the machine without subsequentmovement of the lever 175V from neutral position.

A fuel tank 191 for supplying` fuel to the engine is mounted on thefront end of the main frame 2, anda battery 192 for supplying electriccurrent for starting the engine and to supply the ignition system iscarriedat the rear end of the frame. 4

The machine is provided with front and rear pointers 193 and 194 thatare aligned with the blade to locate the line of travel of the machine.The front pointer 193 constitutes the downturned terminal of a traverserod 195. The rod 195 is adjustable within a sleeve 196 that. is carriedby a Wheel 197. The wheel 197 is carried at a sufcient distanceforwardly ofV the machine so that the in Fig; 3 to the-position shown inFig. 2. The front and rear pointers 193i and 194i are then adjustedlaterally relatively* to' markings on thek surface torbe followed in`making the cut. Attention isparticularly directed to the fact that whenthe machine is being maneuvered into position on the traction'wheels,there is a preferably slight preponderance ofthe weight at the rear ofthe machine so that the forward end of the machine carries the blade outof contact with the surface on which the machine is maneuvered. Afterstarting of the motor 4 the cutting blade is in motion through thedriving connection which includesthe pulleys 30-31 and the driving belt32. The suction connection 136 of the water pump 133 is connected bymeans of a hose with a suitable source of water supply for supplyingwater to the cutting blade when the pump is in operation and the.valve`13 is open. The pump 80 is then actuated Vhy moving the lever 84up and down in the slot 85 to pump hydraulic uid from the case. 81 anddischarge it under pressure into the cylinder 73 through the hoseconnection 33.; The hydraulic fluid upon entering the cylinder of thepump acts between the ram and the. upper head of the. cylinder to bringthe stabilizing wheels39 and dtiof the dolly 35 into bearing Contactwith the surface of the slab A`aud to tilt the frame 2 on the axis ofthe traction wheelsV 10 andV 11 so as to bring the blade 3 into cuttingcontact. The. control lever 158 is then raised to lower the drivingwheels 89 and 90 into contact with the treads of the traction wheels 10and 11. The stop and jam nuts 1-87' and 18S are adjusted on the rod 186,so that when the speed control lever 175 is moved to bring` theV stopnut 187 into contact with the ear 185, the lever 108 of the speedtransformer 106 is shifted to the position which gives the desired speedof the driving wheels 89 and 90.

pointer is in sight of the operator, as later described. This .A

is accomplished by forwardly converging arms 198 and 199 that extendfrom bearing. sleeves 200 and 201,*the bearing sleeves being journaledbetween spaced pairs of lugs202and 203, with fastening devices 202 and203' extending through the lugs and sleeve, as best shown in Fig. 2. Asabove stated,v the rod 195 is adjusted in the sleeve by nuts 20% thatare threaded'. on the rod and en@ gagethe ends of the sleeve 196. Whenthe cutting blade is to be used on the left hand side of the machine,the

rod 195 may be removed and reapplied at the opposite side. The rearvpointers 194'comprise shorter rods 205 that are adjustably mountedV inlugs 206 and 207 projecting rearwardly from the axle 36. The pointedterminals 20S of the pointers are retained in desired position by nuts209 that are threaded on the rods and engage the respective ends of thelugs, asbest shown in Fig. 4. The control levers and mechanismassociated therewith are preferably protected by a guard 210, as shown,in4 Figs. 2 and 4; Y

In operating a machine constructed and. assembled as described, thehandle bars 63 andl69 when lifted upward tilt the machine forward ontraction wheelsi10 and 11, in which position it canbe maneuvered in themanner of a conventional wheelharrow to. permit ymovement of the machineinto position uponthe surface of a concrete 'slab A in which a linearcut B is to be made by the cutting blade 3. The spring 139 is theneiective to suspend the dolly from the frame 2 Awith the stabilizinglwheels 39 and 40. out of contact withthe surface on which the tractionwheels aresupported. Y Y

When the machine is in position, the` wheel 197 carrying 'the frontpointer 193 is lowered from. the position shown Tilting of the frame 2compresses the spring 139 since the collar 141 holds the upper end ofthe spring relatively to the transverse axle 36 of the dolly 35 becauseof the connection of the cable 142. Tilting of the frame results inlifting the lower end of the spring, so that there is a relativemovement between the frame 2 and the collar 141. Therefore, since thedepth indicator drum is also carried by the frame 2 and the cable 151 issecured to the collar 141, the drum is, rotated from its zero positionto indicate the depthof cut through the window opening that correspondswith the diameter of blade being used. The-cutis broughtto the. properdepth by further manipulation. of theV pump levera84as the blade 3penetrates the surface of theA concrete.

In case the blade, should strike a hard spot, or the operator shoulddesire to raise the blade slightly in the cut, the operator releases thepressure from the jack by manipulating, the lever 88 to Vbleed hydraulicfluid from the jaclrcylinder.,l responsive to the preponderance ofweight on the, rear portion of the frame.. The movement of the framequickly forces the hydraulic uid from the cylinder back into the case81.

The. blade may be returned, to the cut to continue the cut under theproper pressure -depending upon the extent to which thel operatormanipulates the pump lever and the release of the fluid pressure fromthe jack. This is animportant feature of` the invention, as it providesfor precision pressure. feed of theV blade into the cut and permits arapid release, of the blade upon release of the pressure,.to protect andprolong the life of the blade.

WhenV the blade is withdrawn from. the cut, the lever 158. is actuatedto effectV lift of the driving wheels 39 and 40. out of contact with the-tread of the traction wheels. Movement ofthe. lever 158 also brings thelug 189 into contact with the lug 190 on the lever 175 to automaticallyactuate the lever 175 to move the lever 108 of the speed transformer Ytozero speed position. Therefore when the lever 15-8.is again actuated tobring the drive wheels into contact with the traction wheels, the lever175 remains in. neutral speed position so that contact of the drivewheels with the treads of the traction wheels does not exertobjectionable reaction forces upon the speed transformer or otherdriving connections. After contact of the driving wheels hasbeenestablished, the lever 175 may then be swung forwardly until thestop nut 187 engages the ear 185, whereupon the lever 108 is returned toits original position for maintaining the desired forward speed of themachine. It is thus obvious that after the desired speed has beendetermined, that speed'is automatically established whenever the lever175 reaches the position where the stop nut engages the ear 185. If itbecomes necessary to change the setting of the lever 175, the stop andjam nuts 187 and 188 may be readjusted on the rod 183 to give the properforward speed of the machine.

- Attention is directed to relatively wider spacing of the stabilizingwheels to give the leverage necessary to prevent the cutting blade fromveering the machine off course. The double stabilizing wheels are alsoimportant to give the desired contact with the slab on which the machineis used. U When the cut is completed, the lever 88 is actuated torelease the hydraulic lluid from the cylinder of the jack and thepreponderance of weight on the rear of the frame produces a downwardmovement of the cylinder to force the fluid from the cylinder into thecase 8l. This movement allows the frame to return to a position wherethe blade is lifted from the cut.

If desired, the machine may be manually maneuvered by the operator, orthe machine may be moved under power by actuating the control levers 158and 175, whereupon the machine is propelled under power of the enginewhile it is being maneuvered and steered into position for making thesubsequent cut.

If there is any tendency of the machine to veer from a straightawaylinear path, this tendency may be eliminated by adjusting relativecontact pressures of the driving wheels S9 and 9i) with the treads ofthe traction wheels. This is readily effected by adjusting the relativepositions of the bearings 92 and 93 on the arms 94 and 95, theadjustment being made by manipulating the jack screws 98 in the properdirection. The amount of pressure on the drive wheels is adjusted byadjusting the length Vof the rod 173.

I-f desired, the cutting blade and guard may be removed from .the righthand side of the machine and applied to the left hand side.

` From the foregoing it is obvious that I have provided a machine whichis well adapted for cutting grooves in concrete slabs and which isconstructed to prolong the life of the cutting blade.

What I claim and desire to secure by Letters Patent is: l.A A mobilemachine for making a linear cut into the surface of a concrete slab orlike structure, said machine including a main frame having a foreportion and a rear portion, a rotary cutter having 'fixed rotationalsupport on the fore portion of the frame on a transverse axis, a pair oftransversely aligned traction wheels having connection with oppositesides of the frame and intermediate said portions for maneuverablysupporting the machine on said surface in which the cut is to be made, adolly having transversely spaced apart stabilizing wheels adapted forrolling contact with said surface, means pivotally connecting the dollywith the frame for retaining the axis of the dolly wheels in parallelrelation with the axes of the'traction wheels and the rotary cutter andtocooperate with said traction wheels in maintaining movement of themachine in a linear direction. a pulley on the rear portion of the mainframe and above the dolly, a cable running over the pulley and havingone end connected with the dolly, a spring yieldingly connecting theother end with a part on the main frame, a coil springv having one endseating on the main frame and the other end connected with the cable forsupporting the dolly with the wheels free of the slab when the mainframe is in a position with the rotary cutter out of contact with theslab whereby the dolly wheels do not interfere with maneuvering of themachine on the traction wheels, a jack connecting thev dolly with therear portion of the main frame including piston and cylinder members,and means for supplying a pressure medium to the cylinder for urging thewheels of the dolly into rolling contact with the slab to cooperate withthe traction wheels in maintaining'saidV straightaway direction onmovement of the machine and to'effect pivotal movement ofthe main frameto bring said rotary cutter into cutting contact with the slab. l l

2. A mobile machine for making a linear cut into the surface of aconcrete slab or like structure, said machine including a-main framehaving a fore part and a rear part, brackets depending from oppositesides of the frame intermediately of said parts, a transverse axlecarried by said brackets,'main wheels rotatable on ends of the axle formaneuvering the machine on the slab and providing a pivotal axis onwhich the frame is adapted to rock, a cutting blade rotatably mounted onthe forward part of the frame, a dolly frame having a transverse axleportion and a forward parallel sleeve portion sleeved over thetransverse axle with ends thereof in contact with the brackets forretaining the axial portion of the dolly in parallel relation and fromlateral movement with respect to said transverse axle, wheels carried onouter ends of the axial portion of the dolly for rotation on an axisparallel with the rotational axis of the main wheels and adapted forrolling contact on the slab to cooperate with the main wheels in holdinga straightaway direction on movement of the machine, a pulley on themain frame above the dolly frame, a cable running over the pulley andhaving one end connected with the dolly frame, a spring yieldinglyconnecting the other end of the cable with the main frame, a coil springseated on a xed part of the main frame and having its oppositejendseating against a collar on the cable for supporting the dolly framewith the wheels thereon free of the slab when the main frame is in aposition supporting the cutting blade out of contact with the slabwhereby the dolly wheels do not interfere with maneuveringof the machineon the main wheels, vand a jack including piston and cylinder membersinterconnecting the dolly frame with the main frame, means for supplyinga pressure medium to the cylinder member for urging the wheels of thedolly into rolling contact with the slab to cooperate with the mainwheels in maintaining said straightawayv direction on movementof themachine and to effect pivotal movement of the main frame to bring saidcutting blade into cutting contact with the slab. i

3. A mobile machine for making a linear cut into the surface of aconcrete slab or like structure, said machine including a main framehaving a fore part and a rear part, brackets depending from oppositesides of the frame intermediately of said parts, a transverse axlecarried by said brackets, main wheels rotatable on ends of the axle formaneuvering the machine on the slab and providing a pivotal axis onwhich the frame is adapted to rock, a cutting blade rotatably mounted onthe fore part of the frame, said rear part of the frame having a greaterweight thereon to hold the main frame normally with the cutting bladeout of contact with the slab, a dolly frame having a transverse axleportion and a forward parallel sleeve portion sleeved on said transverseaxle with ends thereof in contact with the brackets for retaining theaxial portion of the dolly in parallel relation and from lateralmovement with respect to said transverse axle, wheels carried on outerends ofthe axial portion of the dolly for rotation on an axis parallelwith the rotational axis of the main wheels and adapted for rollingcontact on the slab to cooperate with the main wheels in holding astraightaway direction on movement of the machine, a pulley on the mainframe'above the dolly frame, a cable running over the pulley and havingone end connected with the dolly frame, ya spring yieldingly connectngthe other end of the cable with `the main frame, a coil spring seated ona fixed part of the main frame and -having its oppositeendseatingagainstv a collar on the cable for supportingthe dolly frame with thewheels thereon free of the slab when the main frame is in a positionsupporting the cutting blade out of contact with the slab whereby thedolly wheels do not interfere with maneuvering of the machine on themain wheels, and a jack including piston and cylinder membersinterconnecting the dolly frame with the main trame, means forVsupplying a pressure medium to the cylinder member for urging thewheels ofthe dolly into rolling contact with the slab to cooperate withvthe main wheels in maintaining said straight'away direction on movementof the machineV and to effect forward pivotal movement of the mainframelon the axis of the main wheels to bring said cutting blade intocutting Contact with the slab, and means connected with the pulley forindicating control of the pressure medium supply means to maintain agiven depth of cut.

4. In a mobile machine for'making a linear cut into the surface of aconcrete slab or like structure, the combination of a frame, a rotarycutter having xed rotational support on a fore part of the frame,transversely aligned traction wheels, brackets depending from amidportion of sides of the frame, axle means carried by the brackets forjournaling the traction wheels for maneuverably ysupporting the frame onsaid surface in which the cut isto be made and to provide a pivotallaxis on which the frame is adapted to rock, a dolly pivotally connectedwith said axle means and trailing therefrom under a rear partof saidframe and having transversely aligned stabilizing wheels, yieldablemeans connecting the dolly with the frame for suspending the dolly withthe stabilizing wheels out of contact with said surface when the machine`is maneuvered on said traction wheels, and power means connected withthe dolly and a rear partrofV the frame for bringing the stabilizingwheels into stabilizing contact with said surface and' for rockingY theframe' on its pivotal axis, whereby the frame acts as a lever with, thecutter at one end with the power .being applied between the other endand the dollyl to bring the rotary cutter into cutting contact withtherslab while the stabilizing wheels are. bearing upon saidsurface tocooperate with the traction Wheels in maintaining a straightaway coursefor the cutter. y ,n Y Y 5. In a mobile machine for making alinear cutinto the surface of a concrete slab or like structure, the cornbinationof a frame, a rotaryY cutterrhaying fixed rotational support on a forepart of ,the` frame, transversely aligned traction wheels,l bracketsdepending from a midportion of sides of the frame, axle means Ycarriedby the brackets for journaling thetraction wheels for maneuverablysupporting thetrameon said surface in which the cut is to be made and toprovide.V a pivotal axis on which the frame is adapted to rock, adollyfpivotally connected with said axle means and trailingtherefromVund-er a rear part of said trame and having transverselyaligned stabilizing wheels, yieldable means connecting the vdolly withthe frame for suspending the dolly with the stabilizing wheels out ofcontact with said surface when the machine is maneuvered on saidtraction wheels, a fluid pressure actuated jack having a piston memberreciprocable in a cylinder member,v means for connecting one of themembers with the dolly and the other with a tixed part on the rear ,ofVthe frame, means on the frameforrsupplying duid medium under pressure tothe cylinder-to actuate te 'the jack tourge the stabilizing wheels ofthe dolly into cpntact with saidsurface andv for rocking the frame onsaid pivotal Yaxis whereby said trarne- Vconstitutes a lever with thecutte'rpat one end. with the power of said jack applied between theother endand the dolly for urging the cutter into cutting contact by thepower of the jack while the Vstabilizing wheels are-cooperating with thetraction wheels in maintaining a straightaway course for the cutter, andmeans for releasing the fluid medium from the cylinder ot the Vjack forreturning the frame to said maneuvering position to render the yieldablemeans clicctive in4 lifting the dolly. Y

In a mobile machine for making a linear cut into the surface of aconcrete slab or like structure, the combination of a frame, a` rotarycutter having fixed rotational supperton a foregpart of the frame,transversely aligned traction wheels, brackets depending from amidportion of sides of the frame, axle'means carried by the bracketsforv journaling the traction wheels for maneuverably supporting theframe on said surface in which the cut is to be made and to provide apivotal axis on which the frame is adapted to rock, a dolly pivotallyconnected with said axle means and trailing therefrom under a rear partot said framev and having transversely aligned stabilizing wheels, acoil spring having one end seated upon a rear part of said frame, acollar at the other end ofthe spring, a cable connecting the collar withsaid dolly for resiliently suspending the dolly from the frame tosupport the stabilizing wheels out of contact with said frame when theframe 'is to be maneuvered on said traction wheels, a uid pressureactuated jack having a piston member reciprocable in a cylinder member,means for connecting one of the members with the dolly and the otherwith a fixedpart on the rearrof the frame, means on the frame forsupplying iluid medium under pressure to the cylinder to actuatethe jackto urge the stabilizing wheels of the dolly into contact with Vsaidsurface and for rocking the frame on said pivotal axis whereby saidframe constitutes a lever with the cutter at one .end with the power cfsaid jack applied between the other end and the dolly for urging thecutter intoV cutting contact by the power of the jack, while thestabilizing wheels are cooperating with the traction wheels inmaintaining a straightaway course for the cutter, andY means forreleasing the iluid medium from the cylinder of the jack for returningthe frame to said maneuvering position to render the coil spring eectivein lifting thel dolly.V

References Cited in therle of this patent Y VUNITED STATES rnretstrsHackett' y May 5, 1925 1,640,933' Gries Aug. 30, 1927 2.265,354 DahlDec. 9, 1941 2,319,520 Rypkema May 18, 1943 2,468,336 Lewis Apr. 26,1949 -2,634,962 Eglitis Apr. 14, 1953 12,654,339 Sperling Oct. 6, 1953'2,673,725 Coates Mar. 30, 1954 2,716,402r Harrison et al. Aug. 30, 19552,717,775 `aekson 4 Sept. 13, 1955 2,736,544 Wright Feb. 28, 1956 Y'FOREIGN PATENTS 193,876 4' GreatBritain Mar. 8, 1923 551,996 GreatBritain Q Mar. 18, 1943 Y35,877 'Switzerland Dec. 6, 1905

